Work deterrence, inflation, and the tremendous cost would devalue your own currency.
In general most people work jobs solely and exclusively for the $$$. If they didn't need that $$$ they'd have much greater power to negotiate wages. That sounds amazing in theory, but in reality - how much money would it take for you to go scrub toilets when you could otherwise sit and home and live a comfortable life with your family? Probably quite a lot to say the least. Or for a single young guy, how much would you need to pay him to work instead of him being able to play video games and chase tail all day, every day, if he wanted to? And if we're being honest - you can probably remove young as an adjective.
I did add "likely" because I used to be a huge advocate for basic income, but my view shifted on it overtime as I gained a greater appreciation for how economies, and even societies in general, function. Or that the large number of billionaires we have are largely due to accounting and speculation (read: total on-paper capitalization of stock market vastly exceeding the amount of money in existence), rather than them actually just making obscene amounts of money.
I don't see why having to pay significantly more to people cleaning the toilets is a downside. It's a shit job, the pay should reflect that. Of course when people are forced into the treadmill just to get fed, they will take it for pennies, but that doesn't mean that it's the right way to do things.
> how much money would it take for you to go scrub toilets
If my needs were otherwise met, and there were clear instructions allowing me to do this in confidence that I wasn't inconveniencing any users of the toilet, I'd do it free. (Cleaning a toilet is less messy than changing a baby, and that's not hard either.) Given proper PPE, I'd do even more "disgusting" jobs, if they were jobs that needed doing: I draw my line at cleaning up sharps, but that's only because I'm not trained.
Maintaining communal infrastructure is not a thankless task: you can know that everyone who uses the infrastructure until next maintenance time benefits from your work, which is more than most people can say about their jobs. There are people who take pride in their work, even if you consider that work low-status, and beneath you. Do different work, then!
Do you really think most people would live lives of idleness, if not compelled to behave otherwise? If you saw something that needed doing, and you had the means to do it, would you just… walk by? If I may, that says more about you than it does about anyone else.